Not Applicable
The present invention relates to window hardware and more particularly to window sash lock hardware and still more particularly to window sash lock keepers.
Common window sash and rail materials include extruded polymer rails having intricate cross sections, which are designed to accept weather striping, glass and internal reinforcement members. Typical window sash extrusions comprise an exterior surface having slots or protrusions which mate with slots or protrusions in a complementary window rail extrusion when the complementary extrusions are placed in mating proximity to each other, for example by closing a window.
It is well known to employ a manual window sash lock in combination with a keeper to secure a window in a closed position. A moveable locking arm mechanism is typically mounted to a first window extrusion by mechanical fasteners, typically screws, and a keeper is typically mounted to a mating second window extrusion by mechanical fasteners, typically screws, so that the moveable locking arm is positioned to capture the keeper when the window is closed.
It is known that a first window extrusion having a sash lock mounted thereto must be closely aligned to a second window extrusion having a keeper mounted thereto in order for the sash lock to properly capture the keeper. Sash locks and keepers are designed with close clearances to prevent even small relative movements therebetween so that windows are tightly secured when a lock arm engages a keeper. Even small misalignments between a sash lock and a keeper may cause a mechanical interference, which prevents proper motion of a lock arm or proper closing of a window.
It is known that segments of protrusions, which extend from window sash and rail extrusions, are typically cut away in order to provide a flat surface to which a window sash lock keeper may be installed. Corresponding segments of protrusions, which extend from the mating extrusion, are typically cut away to provide clearance for a sash lock keeper when a window is closed. Often machining or cutting operations used to remove protrusions from an extrusion leave a residual protrusion of material or burr on the extrusion surface. Typical sash lock keepers that are mounted to an extrusion surface having a residual protrusion or burr are prevented by the residual protrusion or burr from properly abutting the extrusion surface. Sash lock keepers are often thereby misaligned and cause potential interference with sash lock hardware or a mating extrusion.
Accordingly, the present invention relates to window sash lock keepers having a back surface wherein a linear clearance slot is disposed along the back surface to accept a residual protrusion or burr when the sash lock keeper is mounted to a window sash or rail extrusion.
Common window locking hardware comprises a sash lock and a keeper. The sash lock is typically mounted to a window extrusion rail by a pair of self-tapping screws. The sash lock typically comprises a moveable handle in mechanical communication with a latch arm so that motion of the handle causes some motion of the latch arm. A keeper is typically mounted by a pair of sheet metal screws to a corresponding location on a mating extrusion so that the keeper is located closely adjacent to the sash lock when the window is closed.
A window sash lock keeper comprises a bar of generally solid material having a thickness and at least one through-hole to receive at least one mounting screw. A part of the bar is shaped to form at least one beam capable of being overlapping engaged with at least one moveable latch arm of a sash lock when said keeper is mounted to a window extrusion, the sash lock is mounted at a corresponding location in the mating extrusion and the window is closed so that the extrusions are disposed in close mutual proximity. A window extrusion having a keeper and a corresponding window extrusion having a sash lock define a relative latch path wherein a sash lock arm and/or keeper are constrained to travel as the window is opened and closed. The overlapping engagement of a sash lock arm relative to said at least one beam causes a mechanical interference in the relative latch path, which prevents relative motion of the sash lock and keeper in a window opening direction and thereby prevents relative motion of the mating extrusions in a window opening direction.
Certain extrusions are modified to provide a flat surface area where a keeper may be mounted. Variations in manufacturing processes used to so modify the extrusions often leave a residual protrusion where a section of a linear protrusion has been largely removed. The keeper according to the present invention comprises a back side having at least one slot wherein said at least one slot has a depth that is sufficient to accept most typical residual protrusions in particular window extrusions. Said at least one slot is designed to align with and provide clearance for the residual linear protrusions thereby allowing said back surface of said keeper to lie flat against a flat surface of a window extrusion.
It is to be understood that various changes can be made by one skilled in the art in one or more of the several parts of the invention described herein without departing from the scope of the invention.